Tagged: upconverter

New RTL-SDR + Upconverter Available

BA5SBA, the creator of the Chinese direct sampling kit (and fully assembled version) recently wrote in to let us know about a product that he is now building. His new product is a fully assembled RTL-SDR + Upconverter. The upconverter design uses a DBM balanced ring mixer design which he writes makes less noise and has greater dynamic range. He also writes that compared to direct sampling the upconverter model should have greater sensitivity as it allows use of the R820T LNA. His design uses a 40 MHz local oscillator, comes with increased RF input protection and comes in an aluminium case.

BA5SBA's new upconverter can be found for sale on eBay for around $80 USD.

We also posted previously about BA5SBA's direct sampling kit here.

RTL-SDR + Upconverter in a box by BA5SBA
RTL-SDR + Upconverter in a box by BA5SBA
Example of reception
Example of reception

Understanding Filtering in an Upconverter for the RTL-SDR

Over on YouTube user w2aew has uploaded a video tutorial explaining how filtering in an upconverter works. In a previous video w2aew explained how a simple upconverter for the RTL-SDR worked and noted that for best performance the upconverter needs three filters, one preselector at the input, one after the local oscillator and one after the mixing stage.

In this video w2aew takes a Nooelec Ham-it-up upconverter which has the three filters mentioned above implemented and scopes the output after each filter to show their effect on an input signal.

#175: Filter functions in an HF Upconverter used with RTL-SDR Dongle Receiver

SDR(X): New Upconverter for the RTL-SDR

A new UK designed and manufactured upconverter that goes by the name SDR(X) has recently become available for purchase. This upconverter connects to a RTL-SDR dongle and allows it to receive from 100 kHz up till 1850 MHz. Some of its features include:

  • Four user selectable HF pre-filters (0-2, 2-6, 6-11 and 11 to 30MHz) or single 0-30MHz pre-filter.
  • Band pass filter after mixer and band pass filter after Oscillator
  • User selectable MMIC 18db amplifier external to RTL chip set (lower noise level, than RTL chip and compensates for pre-filters).
  • User selectable HF and VHF/UHF mode (HF 0-30MHz, VHF/UHF mode 24MHz to 1850MHz).
  • Microchip PIC controller for above.
  • Diode protection on RF input.

The board comes as a prebuilt kit which is currently selling for 79.95 GBP which includes an RTL-SDR dongle. The device also comes with complete documentation. The SDR(X) can be purchased from 6v6.co.uk.

Image of the SDR(X)
Image of the SDR(X)

Using a Mixer to Listen to HF on a RTL-SDR Dongle

Over on YouTube user w2aew has uploaded a tutorial video that clearly explains the theory behind upconverters. Upconverters are commonly used with the RTL-SDR to receive the HF (0 – 30 MHz) bands. In the video he shows how to make a simple homemade double-balanced diode ring mixer for the RTL-SDR and shows its performance in HDSDR.

#174: Using a mixer to listen to HF, shortwave, ham, etc. on RTL-SDR dongle

New Japanese HF Upconverter for the RTL-SDR

A new HF upconverter designed for the RTL-SDR has gone up on ttrftech’s Japanese language blog (use Google Translate). The upconverter is called the ‘SC-HFCONV-100’ and comes with 100 MHz oscillator, SMA connectors, USB mini-B power.

Currently the upconverter is only available for sale on the Japanese Amazon store, but it is possible to still order it through the jzool-agent Japanese shopping service.

Japanese HF Upconverter
Japanese HF Upconverter

KN0CK HF Upconverting and Direct Sampling RTL-SDR Receiver Store

In previous posts we have featured Marty KN0CK’s popular modified RTL-SDR dongles which have either a miniature built in high quality HF upconverter with amplifier and filter, or an amplified and filtered direct sampling modification applied to them. With these modified dongles you can receive the HF frequencies from 0.5 MHz to 54 MHz. These kits were previously available for sale on a webstore, however that store has since closed down.

Fortunately, Marty’s modified RTL-SDR dongles are still available at http://www.kn0ck.com/HF_SDR/. The HF upconverting dongle can be bought for $75 and the direct sampling dongle at $60. The store page also shows example videos of the performance you can expect.

KN0CK HF Upconverting RTL-SDR Modification
KN0CK HF Upconverting RTL-SDR Modification
KN0CK HF DIrect Sampling RTL-SDR Modification
KN0CK HF DIrect Sampling RTL-SDR Modification

RTL-SDR HF Preselector Project

Over on YouTube user Theo Faber has uploaded a video showing his adjustable multiband HF preselector project for his RTL-SDR dongle. The preselector covers the entire HF band. Theo designed and built his own homemade upconverter for this project as well.

Preselectors on the RTL-SDR can vastly improve reception quality. Without preselection, noise and strong images of other nearby stations can cause strong interference.

My project ‘pre selector’ for wideband radios and in particular the popular tv-sticks than can be used for SDR reception. The sticks are very cheap and the software free available on the internet. SDR Sharp in this case, is operating stable under XP and W7. Sticks are sensitive, however the input level can only vary +- 20dB. The sticks are easely overloaded and will produce cross and intermediation. So you need in front of the stick / converter band pass or tunable filters. Hopefully this inspired you to build your own set of filters, to fully benefit from the perfect performing of this affordable SDR.
for more info contact me on: t.faber87__AT__upcmail.nl
kind regards and 73’s

SDR RTL dongle and pre selector with HF converter

Nooelec Ham It Up Upconverter Metal Case Now For Sale

Nooelec, manufacturer of the popular Ham-It-Up upconverter has now begun selling metal enclosures for the upconverter. The Ham-It-Up is an upconverter which allows the RTL-SDR to receive HF (0-30 MHz) signals.

  • High-quality custom aluminum enclosure for Ham It Up v1.1 & v1.2.
  • Metal case helps to protect PCB from stray EMI, improving sensitivity.
  • Includes all required hardware to mount your PCB!
  • Ample room inside the case to make modifications and even include a dongle inside the case if you are so inclined.
NooElec Ham-It-Up Upconverter Case
NooElec Ham-It-Up Upconverter Case